I have single story 2 m wide flat-roof extension running down the side
of my end terrace. I've put a pitched roof on it and also extended it
forwards 30cm (or so) to meet the front face of the house. So I need to
extend some of the 5x2 ceiling joists a few inches - they used to rest
on a UPVC porch at the front (now just hanging in mid air). Do I:
1. extend the joists with 5x2/timber connectors into the inner block
wall of the new front cavity wall - issues with heat loss regulation,
and those boot things for the ends of joists are not really retro fit.
2. put a 9x2 purlin across the 2 m width of the extension and hang the
joists from this - awkward.
3. extend the joists with 5x2/timber connectors and hang them from the
new inner block wall of the new front cavity wall with masonary
hangers.

I'd really appreciate some advice. Thank you.